The present invention relates to an improved light radiation device for trapping fish, by which light is radiated into the sea, lakes, or rivers (hereinafter referred to as "sea") in order to attract fish to a certain spot and/or to trap those attracted fish, more particularly to such a light radiation device for effectively and safely radiating light from a source into the sea.
Several techniques are already known for radiating light into the sea from a light source to attract and/or trap fish. One known method is to directly introduce electric bulbs into the sea. With this method, however, there are the problems of broken bulbs, cut cables, electric leakages (short-circuits), and the like. Another known method is to radiate light onto the sea from electric bulbs mounted at the end of an arm projected from a ship. With this method, however, there is the problem of low efficiency light radiation due to loss of light.